Cascading Style Sheets (CSS) is a style sheet language used for describing the presentation of a document written in a markup language such as HTML. CSS is a cornerstone technology of the World Wide Web, alongside HTML and JavaScript.
In CSS, selectors declare which part of the markup a style applies to by matching tags and attributes in the markup itself.
The display
CSS property sets whether an element is treated as a block or
inline element.
The element generates a block element box, generating line breaks both before and after the element when in the normal flow.
The element generates one or more inline element boxes that do not generate line breaks before or after themselves. In normal flow, the next element will be on the same line if there is space